Mobile homes and other wheeled portable structures such as classrooms are structures built in substantially rectangular components at factories, rather than on a site. They are then towed to the location where they will be occupied by homeowners or students or businesses. Because of their large size and wheeled chassis, such portable structures are usually transported by semi-trucks and towed over public highways. They are less expensive per square foot than site-built homes, and being portable, offer great mobility to homeowners, school districts, and businesses requiring temporary or long term structures that can be relocated as needed.
The two major forms of manufactured homes and structures such as classrooms are single-wides and double-wides. Single-wides are sixteen feet or less in width and can be towed to their site as a single unit. Double-wides are twenty feet or more wide and are towed to their site in two separate units, which are then joined together. Triple-wides and even homes and structures with four, five, or more units are also manufactured, although not as commonly.
A common factor with all such portable wheeled structures is their need for towing and their susceptibility to sway and rollover in high winds. High winds can create havoc when towing mobile homes and structures causing oscillations or sudden pulling to one side and with sufficient wind loading, a rollover. For example, if a hard gust of wind hits the towed structure from the left it will thereafter sway and pitch and move to the right.
In cases where winds are exceptionally high such as on the California desert highways, wind gusts can reach more than 70 miles an hour which is a speed sufficient to tear the doors off of cars when they are opened at inopportune times. As most mobile homes and large mobile structures are substantially flat on both long sides, they make a perfect sail to catch the force of such gusts. If the gust is sufficiently strong and of sufficient duration, the force will tilt the towed structure so far as to expose the underside or floor of the structure to the wind. If this happens, the extra torque provided by the wind lifting the bottom of the structure as well as tilting the top of the sidewall of the structure, will cause a rollover. Many double-wide structures have met an untimely demise in the desert winds of the Southwest.
Most professional truck drivers, when presented with high winds, will seek protection from the wind under overpasses or at truck stops or other places of refuge. Thereafter, they will wait the storm out before proceeding. However, on many occasions, such winds arise without warning or exceed predicted velocities, and it is then that even professional drivers will encounter a high risk of rollover of their towed structure.
As noted above, the high winds will first sway the towed vehicle. When that force on one large flat side of the towed vehicle reaches a sufficient load, the wind will begin to lift or twist the towed structure around its long center axis. Generally when one side begins to lift, it will expose the underbelly of the towed structure to the wind in combination with the already tilted side surface. Such a presentation of new surface for windload due to its slanted presentation to oncoming wind will increase the windload and will also provide lift to the structure to rotate it around its center axis. The combination will eventually yield a combined lateral force and lift force to cause a rollover.
However, if the lifting of the floor of the towed structure can be limited or greatly reduced, it will not provide the wind a surface with which to generate extra lateral force and/or lifting force to the structure. Many professional truck drivers have observed that the rearmost portion of the towed structure, behind its axle, is the area most prone to twist to the point that the floor of the structure rotates and begins to generate lift. In order for this rotation to occur on one side of the structure, especially to the rear of the axle, the front corner on the opposite side of the towed structure must dip and move closer to the road surface. Consequently, a dip limiting device which will greatly reduce either front corner of the towed vehicle from dropping toward the road surface would impart force to the structure to resist additional sway and tilt, and would greatly reduce the floor of the structure from rising to become a sail for oncoming wind to generate lift.
While other devices exist that attempt to greatly reduce rollover and sway by imparting a force to the towed structure, most such devices use the axle and frame and biasing thereto in their attempt to limit sway and eventual rollover. While such devices might work with an SUV or large car or motorhome, they have not been employed with great success on large towed structures such as mobile homes or portable classrooms.
As such, there exists an unmet need for a method and apparatus that is easily deployed and engaged to large mobile structures being towed, that will limit the drop of the front corners of that structure toward the road surface during towing to thereby impart force to the structure to limit lifting of the floor on either side. Such a device should be easily engageable to existing conventionally constructed mobile homes. Such a device should be inoperable unless winds of sufficient force cause a drop of the front corners to which it is engaged and should also provide accommodation for road hazards which it might encounter during use.
With respect to the above, before explaining at least one preferred embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangement of the components or steps set forth in the following description or illustrated in the drawings. The various apparatus and methods of the invention are capable of other embodiments and of being practiced and carried out in various ways which will be obvious to those skilled in the art once they review this disclosure. Also, the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
Also, those skilled in the art will appreciate that the conception upon which this disclosure is based may be utilized as a basis for designing of other devices, methods and systems for carrying out the several purposes of the disclosed device. It is important, therefore, that the advantages and claims be regarded as including such equivalent construction and methodology in that they do not depart from the spirit and scope of this invention.